Fire‐Retardant and Thermal‐Insulating Cellulose Nanofibril Aerogel Modified by In Situ Supramolecular Assembly of Melamine and Phytic Acid

Abstract

The widespread utilization of cellulose nanofibril (CNF) has been significantly hindered by its inherent flammability. To explore the potential of using CNF aerogel as sustainable material with good fire‐retardant and thermal‐insulating properties, CNF aerogel is modified by in situ supramolecular assembly of melamine (MEL) and phytic acid (PA). This strategy addresses CNF's flammability and avoids the environment issues associated with the incorporation of traditional fire‐retardant. The modified aerogel exhibits highly porous honeycomb structure with low density and good mechanical properties. After modification with MEL–PA, the aerogel exhibits highly improved shape integrity during burning, higher thermal stability, and favorable combustion behavior for fire retardancy. The heat transfer of the modified aerogel is well hindered, which demonstrated effective thermal insulation performance. In view of the excellent thermal and fire‐retardant properties, the MEL–PA/CNF composite aerogel can be a potential fire‐retardant and thermal‐insulating material for applications such as clothing, building, and electronic devices.

Regulating the coordination capacity of ATMP using melamine: facile synthesis of cobalt phosphides as bifunctional electrocatalysts for the ORR and HER

“…29 All the evidence reveals the fact that there are hydrogen bond and ionic interactions between L1 and L2. 26,30 The Raman spectrum is illustrated in Fig. 1B, where the intensity of the stretching vibrations of P-C (720 cm −1 ), P-OH (978 cm −1 ) and PvO (1025 cm −1 ) in the L1 curve is greatly reduced.…”

“…As the mixture naturally cooled down to room temperature (RT), a supramolecular aggregate was formed. 26 The aggregate was further centrifuged at 8000 rpm and dried at 80 °C for 12 h in a vacuum. The obtained solid product is labelled as L1L2.…”

Closed‐Loop Recyclable High‐Performance Polyimine Aerogels Derived from Bio‐Based Resources

“…[62,65,66] To further investigate the flame retardancy of PIAs and com pare with the reference polyurea aerogel, we conducted initial burning tests by exposing specimens to an open flame for 10 s (Figure 4c and Movies S1−S5, Supporting Information). [67][68][69] After initial ignition, the combustion of PIAA1 and PIAA2 stopped almost immediately, while PIAB1, PIAB2, and reference material burned slightly longer (9−15 s). The fact that the combustion was extinguished in short time can be attributed to the pronounced flame resistance and compact char formation of PIAs (Figure S7, Supporting Information).…”

Metal oxide cluster-assisted assembly of anisotropic cellulose nanocrystal aerogels for balanced mechanical and thermal insulation properties

“…Cellulose nanocrystals (CNCs), mainly extracted from wood and other biomass, are typical renewable biopolymers with abundant resources, 16,17 which provide new possibilities for the construction of thermal insulating materials from supramolecular nanoscale engineering. [18][19][20] It has been reported that weak interactions (e.g., hydrogen bonds and van der Waals interaction) are unfavorable for phonon propagations, 21,22 contributing to the improvement of the thermal insulation performance of CNC aerogels. 5 However, this type of aerogels usually suffers from poor mechanical properties because of their weak inter-connected structural units and resultant unstable skeletons.…”

“…27 Meanwhile, the flammability of CNC-derived aerogels hinders their extensive applications. 18 When facing extreme fire injury conditions, the CNC-derived aerogels with poor fire-retardant performances will easily be burned out. Therefore, it remains a great challenge for the construction of CNC aerogels with balanced thermal insulation ability, fire-retardant performance, and mechanical properties.…”